Reversible air-operated motor



DeC. 426, 1950 H, L. B'owDlTcH A n 2,536,000

REVERSIBLE AIR OPERATD MOTOR Filed Dec. 26, 1947 2 Sheets-Sheet 1 AIR .-b SUPPLY /Z 46 UU Z] 53 2] lNvENToR /4 ATTO EYS H. L. BOWDITCH REVERSIBLE AIR `OPERATED MOTOR Dec. 26, 1950 2 Sheets-Sheet 2 Filed Dec. 26, 194'? 1N EN-ron Haal L owaz'lc/z 3 diaphragm air-operated motor embodying the invention, and arranged so that increasing air pressure moves the valve stem upwardly to open a conventional valve shown partly in section;

Figure 2 shows enlarged and in section the diaphragm motor of Figure 1;

Figure 3 is a side elevation of the motor of Figure 2 looking from the left in Figure 2 and showing parts broken away;

Figure 4 is a front elevation with parts broken away of the motor of Figure 2 but reversed so that increasing air pressure moves the valve stem downwardly;

Figure 5 is a side elevation ofthe motor of Figure 4 with parts broken awayto show the connection between the valve stem and motor;

Figure 6 is a front elevation with parts broken away of another type of air-operated motor em bodying the invention; and v Figure 7 is a side elevation of the motor of Figure 6 and also showing parts broken away.

` Qorresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring to Figure 1, a conventional controller generally indicated at i 3, in response to variations in a thermometer bulb I I, supplies a variable air pressure through pipe I2 to a diaphragm motor generally indicated at I3. Motor I3 has a valve-operating rod vin the form of a valve stem I4, which operates a valve head I5 of a conventional valvegenerally indicated at I3. Valve I6 has an. inlet I1, an outlet I8, and ports I3 whose openings are 1controlled' by valve head I5. As will appear, the motor in Figures l-3 is so set up that when no lair pressure is supplied to motor I3, it holds valve stem |13 down, and holds valve head I5 closed against the seats of ports IS. Variation of air pressure supplied to the motor causes it to move valve head I5 upwardly to different positions and to regulate the flow passed by valve I 5, whichin turn affects the temperature being measured by bulb II The diaphragm motori 3.as set up is an air-toraise motor, operating a valve that opens as the motor raises the valve stem. With this set up increasing air ypressure opens the valve.

ported from valve I6 by a collar 2li iixed to the` valve and a yoke whose rigid supporting legs 2I extend upwardly from collar 25. Referring to Figure 2, the upper ends of legs 2| support legs 22 (also referred to herein as supporting brackets) extending down from circular diaphragm plate 23 forming the lower operating member. Bolts 24 pass through holes in legs 2l, and thread into and secure legs 22 to the yoke and to valve I6.

lResting on plate 23 is a non-metallic impervious circular flexible diaphragm 25, whose edge extends beyond plate 23 and is clamped as at 25 to the outer portion of an inverted cup-shaped circular hood generally indicated at 21 (Figure 1) and forming the upper operating member. To facilitate tight clamping of the diaphragm, hood 2.1 is recessed around its edge to provide annular shoulderl. An annular ring 29 is held tight against the underside of diaphragm 25, and clamps it between the shoulder 28. Bolts 30 pass through ring 29, through diaphragm 25, and through hood 21 beyond shoulder 28 and hold the Such al motoris used when valvev I5 .is controlling fuel' 4 ring, diaphragm, and hood tightly clamped together.

Ring 25 (Figure 2) carries extension 3I which extends inwardly from the ring and terminates in a yoke-shaped end 32 which straddles one of the legs 22 and keeps hood 21 from turning with respect to plate 23.

; Extending upwardly from plate 23 is a hollow tube 33 which performs two functions, one to conduct air pressure to the closure formed by the diaphragm and hood, and the other to provide the mechanical connection between plate 23 and a coil spring31. Tube 33 is threaded into plate 23, and. extends upwardly through a hole in diaphragmv 25 and through a hole 36 in hood 21. A nut 34 and a washer 35 clamp the diaphragm against plate 23'-, toprevent air pressure from escaping'past'the li'oleiiiy the diaphragm where tube l. 33 passes therethrough. Compression spring 31 the legs 22.

surrounds tube 33, pushes upwardly on a washer 39 heldin place on tube 33 byiadjustable nut 40, and pushes down against recessed surface 38 provided on top of movable hood 21.

Over spring 31 and tube 33 is a closing cap or bonnet il iixed to hood 2=1 by bolts 42. Gasket 13 provides a tight seal so that the closure formed by diaphragm 25, hood 21 and bonnet 4I is-airtight, except for the entrance `through tube 33.

Spring 31 thus provides aforce always pushing downwardly en hood 21,v and air pressure in the closure provides a force that pushes upwardly on hood 21 against spring pressure, thereby to lift the hood' and compress the spring. vBy adjusting nut 45 the initial compression of the spring is adjusted, andthe amount of the initial air pressure in the closure required to lift hood 21 from plate 23 (i. e., relatively to move hood 21 and plate 23) is adjusted. It is customary to adjust nut 40 so that three pounds per square inch pressure is required before the hood and plate commence to separate against the force of the spring.

The control air pressureis conducted to the closure through tube 33. `To this end, tube 33 threads into the outlet of a passage 44 formed within a ridge 45 cast on the underside of plate 23. Ridge i5 at its outer end becomes part'of oneof Passage d4 is threaded at its inlet to receive a nipple 46 which serves to connect control pressure conducting pipe I2 with passage 411, and so with tube 33 and the inside of the above'' defi-ned closure.

With the motor constructed as described, when' (the lower operating member) supported by yoke 2l, and when the upward forcev overcomes the downward compression force of spring 31, hood 21'y rises. The amount hood 21`ris'es'depends upon the pressure within the closure, and the amount spring 31 must be compressed to 'balance the upward force exerted by the air pressure. `As the' hood 21 moves up, diaphragm 25 flexes and does'A not resist the upward movement. vGruide yoke 3If prevents therhood 21 vfrom rotating withY respect to the xed platef23.v l

Movement of hood 21 by the air pressure and by spring' 31 is transmitted to valve stem |54 and valve head I5`Iby the following mechanical connection: Referring to Figure 3,I ring 29, is provided with two inwardly-projecting and downggm .wendy-.extendingfoppositely-:disposedrbraeketsml suitably alixed as .by lwelding .the :underside u! the .ring Each bracket :has .a `dow.nwardly exs tending collar .'43, the `collar and ibi-.achat slicing threaded .to .receive bolts 49. ."Bclts `L49.,,-.1.ecure .an adaptor in the 'form :of :a f strap `SII :Ito #brackets spacing sleeves I being .interposed to ifspace lfthe strap downwardly :from sthe `Lbraclrets. .As @shown in .Eigurer2,strap50has -a ahole'fthroughlits center to. receive the threaded aupper :iendsof .Yaluezstem Y I4, f.and upper .and L-.lower .clamping muts si! ahold valve :stem .1;4 :in proper :adjusted frrelatonship to lstrap-.51). A'with this connection, `.Jtertical .inlevement of lhood 211 iis ftransmitpted .toiralve .stem t! and ttovalvelhead :I 5. .As shown-Tin rljguresn :and 2,;afpointer 53 `is.'snitablyeIcn-red:tomaliunsteni :t4

andirbyreference toalstationaryiindexai Tseaweed phragm motor I3 `:are :shown @reversed so fII-hat lin creasing air pressure 'in @the :closure `new `moves .valve stem .lil downwardlyand moveslithe .nowhermally open -valve 'II-.6 tto closed position. In other words, -air `=failure fnow .permits Jspring :131 to r-fmove valve I6 fully :open `and :to '.hold lit fopen. *Toithis end, legs IZlI .ci Vthe fyok-e supported ffrom collar i250 are A'now secured :to and lsupport yhood 21, Vso that r' hood 21is1held rigidfand plate 1123 freerto move'. 'Ifo accomplish Ithis cha-nge, bolts ri tGEigurefZ and bolts 49 :(Figure 3) are removedsandihood 25|, diaphragm Z5 andrplate 523 @are rotated es fa L.unit through l"98" :to ialign ibracleets f4.1 of ring 29 with yoke .legs '-ZI, .whereupon 'bolts *224 .are .inserted @to secure `:ring 2 9 to the woke. "hood 22H Tlis. -now rigidly supported :trom VVvalve iti.

Strap [50 eis `also .rotated .through 90 ito align it .with legs 12,2, .and '.bolts .145. .are ithreadedlginto legs .-122 to connect strap .50 ato `plate '2.3. `Spacing sleeves. '51| `are l:not .used to espace strap I5Il airo'r'n legis A22. zbut .-mere1y-.used.as v:washers :for 'boltslikill This .shift of bracketed] `itc legs :2| is :made l1possible 'by :the `above mentioned lequidistant .spacing .i

is ain .the closure, .Hspring .311 `.pushes upwardly .on

valveistem L4 linzitsupnermostznosition when 1nd artpresurejfzisin the closure, f-i. e., vwhen plate ..23 andlhood 2.1 vare closest together. `To :accomplish athis, "the llengllh `of legs .122, :the .length of spacing `collars and the amount .that brach- `ettsfzltl are: made :to .extend .downwardly from the hood .21 lare `so :selected `.that vwhen .the hood is rotatedoirom .itsiFigureZ positionito its Eig- -ure .4 :positionralthough .fhood :21 actually lowers `v.when.brackets f4.1 Vare boltedto yoke. legs 2y I .strap '50 .fewtually` raised because Aspacing `.sleeves 5I .are no 4doneer eiiective. .In addition to raising strap valve stem I4 is effectively shortenedvby .threding nuts 152 downwardly on it. These :two actions, the raising .of :strap `5.0 .and `the shortening `l`.of yalve .stem .I 4, :raise `valve head al 5 upwardly .completely Ato iopen `.the Avalve when platefirrests ,on-hood '21 .as indicated by lpointer 53 in Figure 5.

-n :the Figures .4 .and .5 construction, since hood |:2-1 is .stationary and plate l23 is movable, the-connection .with the .air `pressure pipe |32 and thezdiarhraem motor is made through nipple 55 threadedinto `the top of `.hood 21, and passage 44 is closed by a suitablenplug e6.

Referring to Figures 6 and 7, the invention is shown applied to o, .different type of motor. In. this .qmotor the 4Lipper and .lower operating members Icomprise upper and lower plates -ll ',andl, .which'plates .are connected by a flexible corrugated annular rubber cylinder 62 whose fendsnreisuitably .secured to the upper and low er 4plates .by .bolts `53 and vby internal .annular clampingrings not shown. As in .Figure 2,-arod .3.3 .(not hollow) .extends upwardly from plate 6I .through -a hole inrplate 62 and carriesa washer 39 which presses on a .compression spring .3.1 which pushes upwardly 0n the rod and down* wardly von .plate BI. .The spring and rod are .covered .by closing Vbonnet 4 I.

As .in the Figure .2 diaphragm motor, spring 31 urges `plates .60 and 6I toward each other. .and increasing pressure separates them against .the yaction .of spring .31. .In rthe arrangement shown .in Figures V6 and 7, lower plate 61 is supported .from yoke legs 2.I "by posts `(brackets) -64 `secured to and extending down `from the -;underside .of plate 5I, and threaded to receive .bolts .55. Movement of upper plate BID is transmitted to valve stern I4 `by a U-brac'ket 66 .which `spans plates 6I! Aand `lil, "passes below plate EI, and which .is .secured to plate El! `by boltsl.

,Bracket 5.5 .passes far enough `below plate .6I :to permit the necessary `relative `movement of plates and 6I.. Bracket 66 is reinforced Vby anges 6I! ,and between the anges and adaptor in the `form `of block 69 is bolted -to the bracket by `bolts .1.0. Block 69 spans an opening 1I through 4bracket 6.6 and has a hole threaded .to receive vvalve stern I4 extending upwardly through Yopening 1I. In this manner, valvestem I4 islcarried Vupwardly when increasing pressure causes the ,plates to separate against .the spring .faction andis :moved downwardly when .decreasing pressure permits theplates `to move together.. A nipple 12 in plate 6I serves to connect air supply gpipe .IZ 4.with the `interior of the motor. Nipple 13 .in .the top 'plate is closed by .a plug.

To :reverse the Aaction `of Vthe motor, bolts 6.5 .are l.witlrrdrawn and .adaptor block .6 9 .is .unbolted fromvbracket i155., and stem I4 is threaded out of theblock. Yoketlegs .2 I .arethenbolted to bracket 6.6. :by :threading 'bolts `lili .into threaded .holes M .in abnacket 165. `Block .'59 is 'turned :on .end and` apegado..

Thus plate B is now rigidly supported, and plate- Spring 3? normally holds 6| is free to move. plate 6| raised, but increasing air pressure lowers plate 6l and moves valve stem I4 downwardly.

As in the Figure 2 construction, when the motor is reversed, the air connection is shifted to the stationary part so that flexing of piping is avoided.

The block 59 serves as an adaptor 'both to make the connection of the valve stem either to bracket 66 or to plate 6l, and to provide the effective change of length of valve stem I4; when the motor is reversed, to change the position oi valve head l5.

Since many embodiments might be made of the present invention and since many changes might be made in the embodiment disclosed herein, it is to be understood that the foregoing description is to be interpreted as illustrative only and not in a limiting sense.

I claim: Y

l. In a pneumatic motor for reciprocating a valve-operating rod and having two opposing in flexible operating members joined to each other by a flexible closure member forming therewith a closed chamber, said operating members-being spring-urged together and being separable along the axis oi reciprocation against the spring action by increasing air pressure within the chamber, in combination, at least two iixed support ing members, a first set of supporting brackets ixed to one operating member and spaced equi* distant from the axis of the valve-operating rod and mountable on said supporting member, a

second set of supporting brackets on the otherl operating member and spaced equidistant fromy said valve-operating rod and from said first set of supporting brackets and being mountable on said supporting members, whereby either of said operating members may be rigidly mounted on i said supporting members leaving the other op* erating member free to move, an air supply conn nection through at least one oi said operating members into Said closed chamber through which air may be supplied to or withdrawn from said erating rod toward the xed operating member,

and when the operating member farthest from the valve-operating rod is mounted on said supporting members, increasing air pressure in said closed chamber moves the other operating member and pushes the valve-operating rodaway from the fixed operating member.

2. In a pneumatic motor for reciprocating "a valve-operating rod and having rst and second operating members joined by a iiexible diaphragm that forms a closed chamber with the rst operating member, and compression coil spring means adapted to urge said operating members together and acting against variable air pressure supplied to said closed chamber which moves said operatingmembers apart, in combination, mechanism for rigidly mounting either of said operating.l members and for attaching the other operating;v member to said valve-operating rod whereby the 3 y motor may be mounted so that increasing air? pressure either moves said first operating member and valve-operating rod in one direction or moves-v the second operating member and valve-operating rodin the opposite direction. said mechanism comprising. a rigid support having at least two supporting members, at least two supporting brackets mounted onsaid rst operating mem-,1 ber `equidistant from said valve-operating rod andmountable on said. supporting members, at 1 least two .supporting brackets mounted on said. second operating member equidistant from said. valveeoperating rod and from the supporting.v brackets on said. rst operating member and 4 mountable on said supporting members, whereby by rotatingV said operating. members as a unit,- either operatingmember may be rigidly mounted 4, on said supporting members, an air supply con,-4 nection through at least one of said operating. members into said closed chamber through which.

air may besuppliedto or withdrawn from said chamber to, operate said motor, an adapton shaped to extend between and be mounted on.

either of said sets of supporting brackets, and a part on said adaptor for connecting said valveoperatingv rod to said adaptor, whereby the operf ating member not mounted on said supporting members may be connected through said adaptor tomove said valve-operating rod. f v

3. In a pneumatic motor for reciprocating a; valve-operating rod and having first and second operating members joined by a ilexible diaphragm thatformsa closed chamber with the rst operating member, and compression coil spring means adapted to urge said operatingmembers together and acting against variab'e air pressure supplied. to said closed chamber which moves said oper-1 ating members apart, in combination, mechanism the second operating member and valve-operating rod in the other direction, said mechanism com-4..

prising, a rigid support having at least two supporting members, a set of supporting brackets mounted on said ilrst operating member equidistant from said valve-operating rod and mountable on said supporting members, a set of supporting brackets mounted on said second oper# ating member equidistant from said valve-operating rod and from the supporting brackets on said rst operating member and mountable on said supporting members, whereby by rotating said operating members as a unit either operaty ing member may be rigidly mounted on said.`

supporting members, an air supply connection through at least one of said operating members through which air may be supplied to and with-- drawn from said closed chamber to operate said motor, anl adaptor shaped to extend between and be mounted on either of'said sets of supporting.; brackets, and a part on said adaptor foricon-v 1 "necting said valve-operating rod to said adaptor,

whereby the operating member not mounted on said supporting members may be connected through said adaptor to move said valve-operat# ing rod, and a guiding yoke extending from one of said operating members and straddling -a attacco bracket extending" from-` the other operating member topreventf relative' rotation between i the upper 'and lower operating members;

4; In a pneumatic motor'for reciprocating a valve-operatingfrod andhaving nrstfand second operating members joined by a flexible diaphragm that1 forms a closed" chamber withithe 'rst operating member, and compression coil spring means adapted to* urge saidV operating members i together and acting-f against variable air pressure supplied* to said closed chamber which moves said operating'members apart, in combination, mechanism forrigidlymounting either ofsaid` operating members and for attaehingfthe other operating memberto said val-vesoperating".

rodwhereby themotor may be mounted" so-that increasing air pressure either moves said rst l operating member and valve-operating rod in one direction or moves the second operating member `and 1 valve-operating f rodf in the other direci tion, said mechanism comprising? ari'gid-support having4 at leasttwo supporting members; a" set of" supportingbrackets mountedionlsaid upper Voperating member equidistant from said valveating members through which air may be supplied to or withdrawn from said`` closed chamber to operate said motor, an adaptor shapeditoextend between and be mountedN on" either of saidsets of supporting brackets, and a part on said adaptor for connecting said valve-operating rod to said adaptor, whereby the operating member not mounted on said supporting members may be connected through said adaptor to move said valve-operating rod, and a guiding yoke extending from said upper operating member and straddling a bracket extending from the lower operating member to prevent relative rotation between the upper and lower operating members.

5. In a pneumatic motor for reciprocating a valve-operating rod and havingwupper and lower operating members joined by a flexible diaphragm that forms a closed chamber with the upper operating member, and compression coil spring means adapted to urge said operating members together and acting against variable air pressure supplied to said closed chamber which moves said operating members apart, in combination, mechanism for rigidly mounting either of said operating members and for attaching the other operating member to said valveoperating rod whereby the motor may be mounted so that increasing air pressure either moves said upper operating member to move said valveoperating rod toward said lower operating member or moves the lower operating member to move said valve-operating rod away from said upper operating member, said mechanism comprising, a rigid support having at least two supporting members, a set of downwardly-extending supporting brackets mounted on said upper` operating member equidistant from said valve-operating rod and mountable on said supporting members, a set of downwardly-extending supporting brackets mounted on said lower operating member equidistant from said valve-operating 10 rodk andI from the supporting" brackets" onA said upper operating memberf'and mountable onf1s'ald operating" members'` as" a unit either operating memberfmay be :rigidly mountedu on said supporting members, an -air supply' connection through each' of said operating members into said closed ch'amb'er "and 'a plugl mem-ber closing thefair supplyfconnection offthe mo'vably 'mounted operating memb'e'rwnereby the air pressure `may alwaysfbe suppliedf` through the rigidly-mounted operating memberand anadaptorsnaped tofextend between and' b'e mounted on either orsaid setsofs`1ip portingflbrackets an'dla parton Asaid adapto'rffr adaptor, whereby the. operating member' not mounted on 1 said@` supporting# members may" be comieaten:` through" saidl adaptor" tot more said valve-operating r'o'd, ahollow tube eXtendintg"up wardly' nein the` center-i or said lower operating member througl'isaid' diaphragm and" into the interior-fof lsaid upper `operai-,ingfneriiber; a reactionpart on said" tube against? whichy l saidf compressiorispring pushes; a' reactionpartf onfsaid upperf operatingmember loca-ted` below thei reaci tion.` part` on` said. tube. andagainst-which said compressiontspringfpasses,` whereby force of said compression. spring4 urges said.n operating members together,A anda passage. in said.lower operating memberY connectingI with saidA tube and forming therewith the air. supply connection throughthe'lowerfoperating member to supplyar pressure to jtlieclosedichamber toiorce `said operating members" apart" against the action of said compressiorrrspring:

6. In a= pneumatic motor frreciprocatinga valveoperating 'rod' and havingupper andilower operating' plates joined? by a flexiblel corrugated cylindrically-shaped bellows that forms a closed chamber with the upper and lower plates, and compression coil spring means within said chamber adapted to urge said plates together against air pressure supplied to said chamber, in combination, mechanism for rigidly mounting either of said operating plates and for connecting the other plate to said valve-operating rod comprising, a rigid support having at least two supporting members, a rst bracket extending downwardly from said upper plate and extending beneath said lower plate and adapted to be mounted on said supporting members, a set of downwardlyextending supporting brackets mounted on said lower plate equidistant from said nrst bracket and adapted to be mounted on said supporting members, whereby either operating plate may be rigidly mounted on said supporting members, an adaptor connectible to said first bracket and to said valve-operating rod when said set of supporting brackets mount said lower operating plate on the supporting members, and being connectible to said lower operating plate and to said valveoperating rod when said rst bracket mounts said upper operating plate on said supporting members, an air supplyconnection through each of said operating plates into said closed chamber and a plug member for closing the air supply connection of the movable mounted plate whereby the air pressure may always be supplied through the rigidly mounted plate, and an opening in said first bracket through which said adaptor passes when connecting said valve-operating rod and said lower plate.

7. In a pneumatic motor for reciprocating a valve-operating rod and having upper and lower operating members joined by a flexible diaphragm that formsa closed chamber. with the upper operating member, and compression coil spring i means adapted to urge saidoperating members 7 together and acting againstvariable air pressure supplied toA said chamber which moves said operating members apart, in combination, mechanism for rigidly mounting either of said operating members and for attaching the other operating member to said valve-operating rod whereby the s motor may be mounted so that increasing air pressure either moves said upper operating member to move said valve-operating rod toward said lower operating member or moves the lower oper- -ating member to move said valve-operating rod faway from said upper operating member, anv air supply connection through each of said operating members into said chambenxand a plug member for closing the air supply connection of the operating member movably mounted, whereby the air pressure ymay always be supplied through the rigidly mounted operating member.

- 8. In a pneumatic motor for reciprocating a valve-operating rod and having upper and lower operating members joined by a flexible diajphragm that forms a closed chamber with the upper operating member, and compression coil spring means adapted to urge said operating members together and acting against variable air `pressure supplied to said chamber which moves jsaidoperating members apart, in combination, mechanism for rigidly mounting either of said operating members and for attaching the other operating member to said Valve-operating rod the lower operating member to move said valveoperating rod away from said upper operating member, said mechanism comprising, a rigid support having at least two supporting members, at least two downwardly extending supporting brackets mounted on said upper operating member and-mountable on said supporting members, at least two downwardly-extending supporting brackets mounted on said lower operating member and mountable on said supporting members, whereby by rotating said operating members as a unit either operating member may be rigidly mounted on said supporting members, an air supply connection through each of said operating members into said closed chamber and a plug member for closing the air supply connection of the movably mounted operating member whereby air under pressure may always be supplied through the rigidly mounted operating member, an adaptor shaped to extend between and be mounted on either of said sets of supporting brackets, and a part on said adaptor for connecting said Valve-operating rod to said adaptor, whereby the operating member not mounted on said supporting members may be connected through said adaptor to move said valve-operating rod.

HOEL L. BOWDIICH.

REFERENCES CITED The following references are of record in the nie of this patent:

UNITED STATES PATENTS Number Name Date 1,841,901 Mabey June 19, 1932 42,208,539 Brown July 16, 1940 2,213,785 Larson Sept. 3, 1940 

